Centrifuge

ABSTRACT

An upright centrifuge has an annular peripheral wall arranged for rotation about a vertical axis and having an open lower end, and a bottom wall adjacent the lower end and movable into and out of sealing engagement with the same. A motor is located beneath the bottom wall and carries the same, the motor with the bottom wall being movable up and down with reference to the peripheral wall. A guide arrangement surrounds and engages the motor so as to permit raising and lowering of the same but to prevent it rotating relative to the peripheral wall, and the guide arrangement has a bottom wall from which a pin or similar projection extends which is engaged by an elastic body fixedly mounted beneath it so as to be urged to a position of alignment with the axis of rotation of the peripheral wall but to be permitted a tumbling movement with reference to this axis.

United States Patent 91 Steimel Oct. 16, 1973 CENTRIFUGE a Prima Examiner-Geor e H. Krizmanich 76 1 t R h as: l H fS g 1 men or gg elme enne leg AttorneyMichael S. Striker 22 Filed: Mar. 8, 1972 ABSTRACT Appl. No.: 232,825

Foreign Application Priority Data Mar. 11,1971 Germany P 21 11712.4

References Cited UNITED STATES PATENTS 10/1962 Andersson 233/27 X 4/1899 Risswuller... 233/27 6/1922 Mauss 233/19 R 5/1919 Sturgeon 233/21 An upright centrifuge has an annular peripheral wall arranged for rotation about a vertical axis and having an open lower end, and a bottom wall adjacent the lower end and movable into and out of sealing engagement with the same. A motor is located beneath the bottom wall and carries the same, the motor with the bottom wall being movable up and down with reference to the peripheralwall. A guide arrangement surrounds and engages the motor so as to permit raising and lowering of the same but to prevent it rotating relative'to the peripheral wall, and the guide arrangement has a bottom wall from which a pin or similar projection extends which is engaged by an elastic body fixedly mounted beneath it so as to be urged to a position of alignment with the axis of rotation of the peripheral wall but to be permitted a tumbling movement with reference to this axis.

12 Claims, 1 Drawing Figure CENTRIFUGE BACKGROUND OF THE INVENTION The present invention .relates generally to a centrifuge, and in particular to a centrifuge having an upright axis of rotation.

Many types of centrifuges are already known, and these include a type wherein the centrifuge rotates about an upright axis and utilizes an annular peripheral wall having a lower open end which can be closed or opened by moving a bottom wall into and out of engagement with it, in that the bottom wall is raised to closure position and lowered to opening position. When the bottom wall is lowered, together with the motor drive shaft on which it is mounted and which rotates it (with such rotation being transmitted via the bottom wall to the peripheral wall when the bottom wall is in closure position) then the bottom wall will move away from the peripheral wall and the latter will be supported on a conical supporting surface provided for this purpose.

The problem with this prior-art construction is that the shaft carrying the bottom wall, which latter is flat and continues to rotate after it has been lowered to open position, is mounted rigidly because of the continued rotation which latter serves the purpose of centrifugally ejecting centrifuged material, for instance sugar so that significant forces act upon the bearings journalling the drive shaft and also the support on which the centrifuge is mounted. These forces are not originated in they unavoidable imbalances occurring in the centrifuge during operation thereof, and thus it is highly undesirable that they should have to be taken into account. Moreover, this known centrifuge construction is not suitable for treating of industrial piece goods and for instance for the removal of oil from metal slivers or fragments, because the drum cannot be rotated at sufficiently high speed. Even with the type of goods which can be centrifuged, for instance sugar, it is necessary if the drum is to be rotated at relatively high speed or is to be filled relatively full to have the drive shaft extend through the entire centrifuge drum and to journal it not only beneath the drum but also above the drum. This of course significantly detracts from the ease of access to the drum and is found disadvantageous.

SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide an improved centrifuge of the type here under discussion.

More particularly it is an object of the present invention to provide an improved centrifuge of upright construction and having an upright axis of rotation.

An additional object of the invention is to provide such an improved centrifuge which has its outlet at the lower end or bottom.

An additional object of the invention is to provide such an improved centrifuge which is of simple construction and requires relatively little space, but which is highly reliable and safe in operation. i

Still another object of the invention is to provide such a centrifuge which permits simple and rapid filling and removal of the material to be centrifuged, and which is particularly (although not exclusively) suitable for deoiling, washing or drying of industrial piece goods, such as small components of metal or synthetic plastic, castings,-stampings, as well as the de-oiling of metal slivers or fragments resulting from turning or similar opera tions.

In pursuance of these objects, and others which will become apparent hereafter, one feature of the invention resides in the centrifuge which, briefly stated, comprises an annular peripheral wall arranged for rotation about an upright axis and having an open lower end. A bottom wall is located adjacent the lower end and motor means is located beneath the bottom wall and has an output shaft connected with the same for rotating the bottom wall about the aforementioned axis. Shifting means is provided for raising the motor means to a first position in which the bottom wall closes the open lower end and is coupled with the peripheral wall for rotating the same, and for lowering the motor means to a second position in which the bottom wall is downwardly spaced from the lower open end. Guide means engages the motor means and guides the same for raising and lowering but prevents rotation of the motor means, such guide means having a lower end wall extending transversely of the axis of rotation. Elastic means is fixedly mounted beneath the guide means, and a projection projects centrally downwardly from the end wall of the guide means into engagement with the elastic means so as to be permanent urged by the same to a position of coincidence with the axis of rotation.

Thus, the motor means, guide means and projection can in effect tilt transversely of the axis to a limited extent, with the lower end which is engaged by the elastic means moving radially of this axis when such tilting occurs, but being urged back to a position of coincidence with the axis by the action of the elastic means.

It is advantageous for the carrier for the motor means, which is guided in the guide means, to be hydraulically raised and lowered, with the projection being a hydraulic cylinder in the interior of which a rod-like piston is guided which is connected with the motor carrier and raises and lowers the same and thereby the bottom wall of the centrifuge.

At the upper end of the guide means, which is constructed as a guide housing, there is provided an annular or ring portion which diverges conically in downward direction and cooperates with a correspondingly configurated surface on the motor carrier when the bottom wall is in its closure position in which it closes the drum and is coupled with the same for rotation thereof. This provides for a reliable and vibration-free connection between the drum (which is in operative position) and the projection.

A cylindrical ring is located beneath the conical surface of the peripheral drum wall which engages with the surface of the ring portion, and this cylindrical ring slides along a cylindrical guide wall portion provided at the outer periphery of the bottom wallwhen the latter moves between its first and second positions.

The invention also makes provision for simple and reliable insertion and-removal of material. To provide for improved insertion of material a closable funnelshaped filling hopper is located above the peripheral wall of the centrifuge, and because its outlet can be closed it is possible to fill this hopper while the previous charge in the centrifuge is being centrifuged and removed. Conversely, the removal of the material is effected via a funnel-shaped member located beneath the centrifuge drum and into which the centrifuged material will slide when the bottom wall of the drum is lowered so as to open the lower end of the peripheral wall. It is advantageous to connect the downwardly convergent funnel-shaped outlet member with the guide housing for the motor, and to have the upper edge of the funnel-shaped outlet member extend to the level of the ring on which the drum or rather the peripheral wall of the drum will rest when the bottom wall has been lowered. It is further advantageous if the centrifuge housing surrounds this ring and the upper periphery of the funnel-shaped outlet member with sufficient space so as to permit tumbling movements of the funnelshaped outlet member without interfering therewith, so that the vibrations of the drive motor and the drive shaft are transmitted to the funnel-shaped outlet member but not to the centrifuge housing.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE is a vertical section through a centrifuge according to the present invention, showing the centrifuge in closed condition in the left half of the drawing and showing it in open condition in the right half of the drawing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS It will be seen that the centrifuge construction which is illustrated in the exemplary embodiment of the drawing has a circumferential or peripheral centrifuge wall or drum wall 2, having an open lower end which can be opened and closed by engagement with the wall 2 of a upwardly convergent conical bottom wall 1. The centrifuge rotates about an upright -normally a vertical axis and the bottom wall 1 is mounted on the output shaft 3 of a drive motor 4. The drive motor 4 is mounted in a guide housing 5 and can be shifted axially of its output shaft 3, that is it can be raised to a position in which the bottom wall 1 enters into the lower open end of the peripheral wall 2 and closes this lower open end, at the same time engaging the peripheral wall so as to entrain it for rotation, and a lower position in which the bottom wall 1 is downwardly withdrawn from the peripheral wall 2 and opens the lower end as shown at the right-hand side of the drawing.

The guide housing 5 has a transversely extending bottom wall on which a projection 7 is mounted coaxially with the output shaft 3. This projection 7 is supported via a calotte-shaped portion 8 on a similar colotteshaped portion 10 provided in the base or support member 9 of the centrifuge. Elastically yieldable means, here illustrated in form of an elastomeric body 11, surrounds the projection 7; in the illustrated embodiment the body 11 is of annular configuration and is accommodated in a cylindrical sleeve 12 of the socket 9, supporting the projection 7 against radially acting forces so as to permit a radial tumblingmovement of the projection 7 but urging the latter permanently back to its position of alignment with the normal axis of rotation. The housing 13 of the centrifuge is connected with the socket 9, here at the outer edge thereof.

As the drawing shows, the peripheral wall 2 has a lower upwardly divergent portion 14 which is provided at its upper edge with a ring flange l5, and with a downwardly divergent upper portion 16 having at its lower edge an additional ring flange 17. These flanges 15 and 17 are secured to one another in suitable manner forming no part of the invention, but in such a manner that space will remain between the flanges l5 and 17 through which the liquid removed from charge by centrifuging can escape. A screen 19 is located at the inner side of the wall 2, overlying these openings and covering the gap between the flanges 15 and 17 so as to prevent the centrifugal ejection of centrifuged material.

A portion 21 in effect serves as a catch basin and has an inner cylindrical edge 20; it is connected to the housing 13 and thering flange 15 extends over the edge 20 so that ejected liquid is guided into the outlet 22 and cannot reach the funnel-shaped outlet member through which the centrifuged material is to be removed. This separation effect is made still more reliable by providing the outer edge of the ring flange 15 with a downwardly extending cylindrical ring portion 23 which extends over the portion 20, the latter having a smaller diameter and projecting upwardly. The portion 20 is spaced from the wall of the ring portion 23 and of the portion 14 of the wall 2 to such an extent that the drum can perform the necessary tumbling movements which are unavoidable during rotation for centrifuging purposes. The upper edge 24 of the portion 16 is inwardly directed at an inclination of approximately 45 and prevents an ejection of centrifuging material from the drum.

It will be appreciated that when the bottom wall 1 engages the wall 2, they must be in proper contact. On the other hand it is necessary that when the wall 1 is downwardly withdrawn from the lower open end of the wall 2, the wall 2 must be suitably supported because otherwise it would simply move down with the wall 1 and the desired separation of the two walls -and opening of the lower endwould not occur. As the drawing shows, the lower end of the wall 2 is provided at the inner side with a conically downwardly divergent surface 26 of annular configuration, and the periphery of the bottom wall 1 is provided with a similarly contoured annular surface 27 which can engage the surface 26. One of the surfaces 26 and 27, in the illustrated embodiment the surface 27, is provided with an elastomeric sealing member 28 which is here partly recessed into the surface 27 and which will sealingly contact the surface 26 when the bottom wall 1 closes the lower open end of the wall 2. The inclination of the surfaces 26 and 27 with reference to the horizontal is between substantially an angle which in connection with the provision of the elastomeric sealing element 28 and the weight of the wall 2 itself, makes it possible to transmit from the wall 1 into the wall 2 the torque necessary for acceleration and deceleration.

The drawing also shows that in the lower region the wall 2 is slightly inwardly extended so that the weight of the charge itself also serves to press the wall 2 against the sealing element 28, to thereby obtain a still better sealing effect. Downwardly from the edge of the wall 1 there extends a cylindrical guide wall portion 29 which in the illustrated embodiment is provided with recesses (of suitable configuration) so that it is formed with for instance eight but at least three circumferentially distributed guide ribs 30 which contact a cylindrical ring 25 at the lower end of the wall 2 in order to guide and orient the latter. The ring 25 is of relatively significant wall thickness and according to the invention should have a mass which corresponds to approximately one third of the mass of the wall 2 itself.

As pointed out before, the wall 2 must be supported against downward movement when the wall 1 is to be withdrawn from it to open its lower end. For this purpose the wall 2 is provided at its lower edge 25 with a conical annular surface 32 and downwardly below the wall 2 there is located a conical ring 31 whose conicity corresponds to that of'the surface 32. Thus, when the wall 1 is lowered the wall 2 will engage the ring 31 with its surface 32 before the wall 1 has been lowered to the full extent, with the result that further lowering of the wall 1 results in movement downwardly away from the lower end of the wall 2.

The ring 31 itself is supported by the upper end of a funnel-shaped outlet member 33 having an outlet 34 and a wall 35 which is inclined from the upper end to the outlet 34 and is connected with the housing 5. The member 33 is spaced from the centrifuge housing 13 to such an extent that it will not contact with the same when tumbling movements occur. Above the outlet opening 33 a substantially roof-shaped member 36 is mounted in the member 33, in order to decrease the height through which the centrifuged material must fall when it slides off the wall 1. At the same level, located at the side of the housing 5 remote from the outlet opening 34, is a further roof-shaped member 37 which prevents the centrifuged material from adhering and being retained.

The insertion of material into the drum is also facilitated by locating on the housing 13 above the wall 2 a funnel-shaped inlet or filling hopper 38 whose maximum cross-section corresponds to the cross-section of the housing 13 and whose outlet opening corresponds in diameter to the diameter of the other drum opening 39. A conical member 40 is located in the hopper 38 and can be raised and lowered with reference to the outlet opening thereof, so that it can open and close the outlet opening as desired. A cylinder and piston arrangement 41 is provided which is of hydraulic or pneumatic type and located within the member 40, being supported by a member 42, so as to raise and lower the member 40 as desired. With this arrangement the outlet of the hopper 38 can be closed with the member 40, and the hopper be filled with the material for the next charge, while the centrifuge still processes the previous charge and while it discharges the centrifuged material. This means that the sequence of operations can be increased substantially. Moreover, the configuration of the hopper 38 and of the member 40 assures an even charging of the centrifuge drum so that the possibility of an excessive imbalance of the drum is at least reduced if not entirely avoided.

Various different drives may be used for the motor 4. It is for instance possible to use a hydromotor mounted on a motor carrier 43 which can be raised and lowered andwhich is guided at its periphery in the guide housing 5. A piston 44 is connected with the carrier 43 coaxial with the output shaft 3 of the motor 4. The piston 44 is slidable axially in a bore 45 provided in the projection 7 which is thus the cylinder for the piston. Pressure fluid may be supplied via the conduit 46 and the construction may be of hydraulic type. When the pressure fluid is supplied, it enters into a space between the bottom wall of the bore 45 and the lower end of piston 44, lifting the piston 44 and thereby pushing the carrier 43 against an abutment ring 47 provided at the upper end of the housing 5, to assure a reliable vibration-free connection between the carrier 43 and the housing 5 in the operative position. The ring 47 is provided with a conically downwardly converging annular surface which cooperates with a correspondingly configurated annular surface 48 at the periphery of the carrier 43.

The operation of the centrifuge will already be evident from what has been set forth. The hopper 38 has its outlet closed with the member 40 and is then filled with a charge of the material to be centrifuged. When the bottom wall 1 has been moved into engagement with the wall 2, and thereupon the two have been raised to operative position, by insertion of pressure fluid into the cylinder and raising of the piston 44, so that they move from the position shown in the right-hand side of the drawing to that shown in the left-hand side of the drawing, the drum is rotated at low speed. During this movement the member 40 is raised by the cylinder 41 so that the charge in the hopper 38 can enter evenly distributed into the slowly rotating drum composed of the walls 1 and 2. When the charge has entered the drum the member 40 is moved to closure position and a new charge can be admitted into the hopper 38, while at the same time the drum is now rotated at high speed in order to effect the centrifuging operation. When the drum has been rotated for the requisite period of time its rotation is braked and the wall 1 is now lowered. lnitially the wall 2 moves downwardly with the wall 1 until its surface 32 contacts the ring 31 so that during further lowering of the wall 1 the same moves out of the open end of the wall 2, opening this open end and moving to the position illustrated in the right-hand side of the drawing. In this position the centrifuged material can move into the outlet hopper 33 and move to the outlet thereof.

The next charge is already accommodated in the hopper 38 so that immediately after the centrifuged material has left the drum the bottom wall 1 can be raised again and as soon as the walls 1, 2 are in the operative position shown in the left-hand side of the drawing the member 40 can be moved to open position and the next charge can be admitted into the drum. Because the cross-sections of the inlet in the hopper 38 and in the outlet in the hopper 33 are rather large, the charging and unloading of the drum takes very little time and this, combined with the precharging of the hopper 38 during centrifuging of the previous charge in the drum, greatly facilitates production speed.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a centrifuge, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can be applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is:

l. A centrifuge, comprising an annular peripheral wall arranged for rotation about an upright axis and having an open lower end; a bottom wall adjacent said lower end; motor means beneath said bottom wall and having an output shaft connected with the same for rotating said bottom wall about said axis; shifting means for raising said motor meansto a first position in which said bottom wall closes said lower open end and is coupled with said peripheral wall for rotating the same, and for lowering said motor means to a second position in which said bottom wall is downwardly spaced from said lower open end; guide means engaging said motor means and guiding the'same for raising and lowering but preventing rotation of said motor means, said guide means having a lower end wall extending transversely of said axis of rotation; elastic means fixedly mounted beneath said guide means; and a projection projecting centrally downwardly from said end wall into engagement with said elastic means so as to be permanently urged by the same to a position of coincidence with said axis.

2. A centrifuge as defined in claim 1, said projection being a hydraulic cylinder and accommodating a piston; further comprising a mount for said motor means, located in said guide means for raising and lowering relative thereto and carrying said motor means; and wherein said piston is connected with said mount.

3. A centrifuge as defined in claim 1, said guide means being a guide housing having an upper endportion; further comprising a mount for said motor means, located in said guide housing for raising and lowering relative thereto and carrying said motor means; an annular portion on said upper endportion and having an outer conically downwardly diverging surface; and a contact face on said mount configurated for mating engagement with said surface and adapted to contact the same when said mount is raised.

4. A centrifuge as defined in claim 1, said guide means being a guide housing; further comprising a ring mounted beneath said peripheral wall and configurated for engaging and supporting the same when said bottom wall is moved to said second position; and a funnel member mounted on said guide housing, said funnel member having a lower outlet and an upper inlet bounded by a marginal portion which carries said ring.

5. A centrifuge as defined in claim 4, further comprising a centrifuge housing surrounding said walls and spaced from said funnel member so as not to interfere with tiltings movement performed by the same relative to said axis of rotation.

6. A centrifuge as defined in claim 1, said peripheral wall having in the region of said lower end a support surface; and further comprising a cylindrical guide ring beneath said surface; and wherein said bottom wall has a contact face adapted to engage said support surface, and a cylindrical guide wall portion below said contact face and matingly cooperating with said guide ring.

7. A centrifuge as defined in claim 6; further comprising an additional support surface provided on lower edge of said guide ring.

8. A centrifuge as defined in claim 6, said guide ring having a mass which is equal to about one third of the mass of said peripheral wall.

9. A centrifuge as defined in claim 6; and further comprising recesses provided in said guide wall portion and forming guide ribs thereon.

10. A centrifuge as defined in claim 1, said peripheral wall and said bottom wall having respective cooperating annular conical contact faces which each include with the horizontal an angle of between substantially and further comprising at least one annular sealing element of elastomeric material provided on at least one of said contact faces.

11. A centrifuge as defined in claim 1; further comprising a funnel-shaped filling hopper for said centrifuge, said hopper having a major cross-section corresponding substantially to that bounded by said peripheral wall, and a minor cross-section at its outlet which corresponds substantially to that of an opening at the upper end of said peripheral wall.

12. A centrifuge as defined in claim 11; further comprising an upwardly convergent conical closure member in said hopper adapted to move into and out of said outlet for respectively closing and opening the same;

and moving means for moving said closure member. 

1. A centrifuge, comprising an annular peripheral wall arranged for rotation about an upright axis and having an open lower end; a bottom wall adjacent said lower end; motor means beneath said bottom wall and having an output shaft connected with the same for rotating said bottom wall about said axis; shifting means for raising said motor means to a first position in which said bottom wall closes said lower open end and is coupled with said peripheral wall for rotating the same, and for lowering said motor means to a second position in which said bottom wall is downwardly spaced from said lower open end; guide means engaging said motor means and guiding the same for raising and lowering but preventing rotation of said motor means, said guide means having a lower end wall extending transversely of said axis of rotation; elastic means fixedly mounted beneath said guide means; and a projection projecting centrally downwardly from said end wall into engagement with said elastic means so as to be permanently urged by the same to a position of coincidence with said axis.
 2. A centrifuge as defined in claim 1, said projection being a hydraulic cylinder and accommodating a piston; further comprising a mount for said motor means, located in said guide means for raising and lowering relative thereto and carrying said motor means; and wherein said piston is connected with said mount.
 3. A centrifuge as defined in claim 1, said guide means being a guide housing having an upper endportion; further comprising a mount for said motor means, located in said guide hoUsing for raising and lowering relative thereto and carrying said motor means; an annular portion on said upper endportion and having an outer conically downwardly diverging surface; and a contact face on said mount configurated for mating engagement with said surface and adapted to contact the same when said mount is raised.
 4. A centrifuge as defined in claim 1, said guide means being a guide housing; further comprising a ring mounted beneath said peripheral wall and configurated for engaging and supporting the same when said bottom wall is moved to said second position; and a funnel member mounted on said guide housing, said funnel member having a lower outlet and an upper inlet bounded by a marginal portion which carries said ring.
 5. A centrifuge as defined in claim 4, further comprising a centrifuge housing surrounding said walls and spaced from said funnel member so as not to interfere with tiltings movement performed by the same relative to said axis of rotation.
 6. A centrifuge as defined in claim 1, said peripheral wall having in the region of said lower end a support surface; and further comprising a cylindrical guide ring beneath said surface; and wherein said bottom wall has a contact face adapted to engage said support surface, and a cylindrical guide wall portion below said contact face and matingly cooperating with said guide ring.
 7. A centrifuge as defined in claim 6; further comprising an additional support surface provided on a lower edge of said guide ring.
 8. A centrifuge as defined in claim 6, said guide ring having a mass which is equal to about one third of the mass of said peripheral wall.
 9. A centrifuge as defined in claim 6; and further comprising recesses provided in said guide wall portion and forming guide ribs thereon.
 10. A centrifuge as defined in claim 1, said peripheral wall and said bottom wall having respective cooperating annular conical contact faces which each include with the horizontal an angle of between substantially 70* - 80*; and further comprising at least one annular sealing element of elastomeric material provided on at least one of said contact faces.
 11. A centrifuge as defined in claim 1; further comprising a funnel-shaped filling hopper for said centrifuge, said hopper having a major cross-section corresponding substantially to that bounded by said peripheral wall, and a minor cross-section at its outlet which corresponds substantially to that of an opening at the upper end of said peripheral wall.
 12. A centrifuge as defined in claim 11; further comprising an upwardly convergent conical closure member in said hopper adapted to move into and out of said outlet for respectively closing and opening the same; and moving means for moving said closure member. 